Definitely rotala varieties! It grows like hell in my super low light tank, faster than even hornwort. Ludwigia... not so much. I'd call it a low-medium light plant and it can be fussy about other factors given only low light. Also, though not a stem and not what you asked, vallisnaria.
Anubias species, Java Ferns are undemanding but they're not stem plants
I dont know whats wrong. Wisteria and water sprite just failed. Although my crypt aponogetifolias kept on thriving same too with swords. Bacopa was tried but melted. Sunset hygro, it thrived but turns green and grows a bit slowly.